Tuesday, 22 July 2025

Mapping Mountains – Trimble Surveys – Yr Wyddfa


13.05.25  Castell (SH 625 512) 

Castell (SH 625 512) 

A day in the company of Mark Trengove and John Kirk investigating Cwm Llan with a small prominence hill thrown in to keep the surveyor happy.  Cwm Llan is impressive and almost alpine like as it heads skyward from the confines of Nant Gwynant.  This cwm eventually butts up against the southern face of Yr Wyddfa, which is mainly hidden on the lower section of the Watkin Path due to the bulk of Yr Lliwedd as its south-western façade tumbles down toward the upper cwm.

The continuing high pressure system gave idyllic conditions, with a welcome slight breeze, beautiful blue sky and warmth predominating.  We had a number of objectives during our planned walk and were at the car park and starting our ascent of the Watkin Path by 11.20am. 

The south face of Yr Wyddfa

The car park is positioned at approximately 80m in height and therefore the Watkin Path gives the greatest ascent of any of the six major walking routes leading to the summit of Wales’ highest peak.  In its lower part are a series of waterfalls and these today were gathering the masses with a number of bikini clad young ladies venturing up the path.

We had no intention of aiming for the delights of the summit of Yr Wyddfa, but planned on reaching the upper quarry and examine the rocks hereabouts as well as on our route up. 

The start of the Watkin Path

The Watkin Path was built under the guidance of Sir Edward Watkin, who in the late 1800s had purchased the southern side of Yr Wyddfa and built the Chalet; his residence in North Wales.  Watkin was a remarkable person and the Wikipedia page dedicated to his life is a much better place to read of his exploits rather than any I could attempt to write.

Unfortunately the Chalet burnt down in 1960, but we wanted to find its remains and also examine the rocks close by.  Our interest in the rocks en route was partly based on having two enthusiastic geologists in our midst, the third person being the surveyor and blogger. 

The greens of early summer

The initial route up the path was beautiful in late morning dappled light casting through the greened trees, giving both intimacy and welcome shade.  John had pinpointed where the remains of Watkin’s Chalet were and they are easily found, being straight beside the path just before it joins another path heading up from the lane that leads to the farm of Hafod y Llan. 

The flat grassed area that was once the front garden of Walkin's Chalet

We investigated the remains for quite sometime, finding the stone walled corner of the building as well as the old stove, which was now upturned on top of one of the two small piles of discarded remains, now forgotten amongst a plethora of bricks and debris.

It was here that Gladstone stayed when he visited Sir Edward and officially opened the path to the summit.  The plaque commemorating the event is pinned to what is known as the Gladtone Rock and was one of a number of things we wanted to visit during our exploration; however this exploration mainly consisted of taking fragments of rock for later analysis, all of which were labelled and bagged. 

The old stove, now upended

We stopped for lunch under an outcrop of rock just above the remains of Watkin’s old residence.  It was shaded here and relatively quiet with just a few people heading down from the hill and a few also heading up.  We waved and asked where they were heading to and from; many that were heading up were aiming for the stream and waterfalls having seen them on TikTok.

After lunch we continued up out of the shaded confines of the lower wooded area and now in to the direct sunlight, which remained with us for the majority of the day ahead, only disappearing due to the relative lateness of our descent. 

The continuation of the path leading to the waterfalls

We broke off from the main path before the waterfalls and headed toward a small prominence hill beside the steep disused incline that wedged its way through the bwlch of the hill.  This incline would at one time have been used in conjunction with one of a number of working quarries that dot the upper cwm.

The recorded name of the hill is Castell and it looked attractive from our approach, with steep sides of rock and grass and newly sprouted fern and bluebells as accompaniment.  As I headed up, John settled in the shade of the flat bedded incline at the bwlch, whilst Mark followed me. 

The view of Yr Wyddfa and the waterfalls from Castell

The top of the hill had a couple of candidates for high point, each relatively close to one another.  I chose my spot for high point and proceeded to assemble the Trimble to gaher summit data.  As it quietly beeped away gathering its individual datum points I stood a safe distance away so as not to disturb satellite reception, scribbled all necessary detail in my surveying notebook and admired the view down to Nant Gwynant and up toward the summit of Yr Wyddfa.  It really was a marvelous place to be on such a beautiful day, and one that can only have an occasional visit from a rogue hill walker or two. 

Gathering data at the summit of Castell

Once the Trimble had done its stuff I hesitantly made my way down through the stepped rock and joined John and Mark in the shade for late lunch and conversation.  We still had a bit of ascent to do until reaching the top quarry and therefore after packing everything away we headed back to the main path and up past the series of waterfalls and bathers. 

The path above the waterfalls

On our way to the upper quarry we visited the Gladstone Rock.  This is where William Ewart Gladstone, who at the time was aged 83 and serving his fourth term as Prime Minister, spoke to the gathered masses of Eryri and for want of a better phrase declared the Watkin Path open. 

The plaque commemorating Gladstone's visit

I was looking forward to another shaded rest when we reached the memorial plaque, but all too soon we were off upward, following the path as it headed beyond the upper waterfalls to the quarry masters old residence and the upper quarries beyond the great spur of Craig Ddu, which plummets downward from the south-western façade of Y Lliwedd. 

The quarry master's old residence

It was here we rested, but not for long as Mark had his eye on a large rock around the upper cwm that had no doubt deposited itself from the ridge of Allt Maenderyn above, so as he headed off John and I sat in shade, chatted and relaxed. 

Heading toward the upper quarry

Mark was gone for 30 minutes or so, we watched him make progress toward his boulder and then heard the distinct sound of hammer on rock as another sample was bagged and labelled.  As he started his descent back toward us John headed up to an intermediary high point waiting his return. 

Yr Aran

All that remained was the descent to the valley below.  An easy thing to write, but by now the toil in the sun had taken its toll and on the lower section I suffered as sweat continued to bubble from my brow and my steps were getting shorter in length as my willpower ebbed.  However, I’ve encountered many such descents and all one has to do is put one step in front of the other and eventually the car is reached. 

The south face of Yr Wyddfa

Having arrived at the car I changed quickly in to dry clothes and we headed down valley to the delights of a welcome meal in the Prince Llewelyn pub.  After the meal Mark drove back to Mold and I eventually arrived home just before midnight.  It had been a long but very rewarding day.

 

Survey Result:

 

Castell                                        

Summit Height:  157.2m (converted to OSGM15, Trimble GeoXH 6000)

Summit Grid Reference:  SH 62554 51296 (Trimble GeoXH 6000)

Bwlch Height:  147.2m (LIDAR)

Bwlch Grid Reference:  SH 62525 51293 (LIDAR)

Drop:  10.0m (Trimble GeoXH 6000 summit and LIDAR bwlch)

Dominance:  6.36% (Trimble GeoXH 6000 summit and LIDAR bwlch)

                                       

 

For further details please consult the Trimble Survey Spreadsheet 

No comments: